Beaty:
Your question posed the scenario of those "contemplating paedophilia", whatever that means?
Have you ever, for example, heard of an offence called "Threats To Kill"? It can, in certain circumstances, carry a life sentence. (usually carries 10 years).
I'd suggest that those "contemplating paedophilia" fall into a similar category, for as far as I'm concerned the planned defilement of a child is no different: a life would be ruined forever.
And given the fact that the authorities would at some point release a convicted paedophile back amongst the unsuspecting public, my solution for the enforced removal of the paedo's sexual organs would at least ensure that they could not re-offend.
Having some well meaning shrinks, social workers and probation officers telling them not to do it again is akin to waving a red rag at a bull and in no way protects any vulnerable would-be-victim from the predatory instincts of a subhuman who still has the "tools"(no pun!) with which to do the job (again and again) ad infinitum.
The victim's rights must always supercede those of the offender, which is all too often not the case in this country.